1. Field of the Invention
This invention relates to devices which are used to insert a sewer snake into a drain line or sewer pipe for the purpose of removing obstructions in the line or pipe.
2. Description of the Related Art
In prior art, the sewer snake has been contained in a canister which is rotated (U.S. Pat. Nos. 2,042,407, 2,237,880, 3,897,602).
Telescopic devices have been used to advance the snake into the pipe (U.S. Pat. Nos. 2,042,407, 2,237,880, 3,897,602, 1,796,340, 4,364,140).
A canister arrangement is generally quite heavy and difficult to maneuver. Because of the moment of inertia of the rotating canister and the coil of snake inside, the device will continue to rotate even after power to the rotating motor is interrupted. This may damage the snake if it has become stuck in the pipe.
Lawrence F. Irwin suggested a telescopic device described in U.S. Pat. No. 4,364,140. This provides an efficient means for advancing a length of snake down a pipe. However, to advance long lengths of snake, the snake must be made of segments which are coupled together.
Disadvantages of this are:
1. The snake is much more expensive than an ordinary single piece sewer snake because of the coupling devices required.
2. The coupled segments of the snake decrease the flexibility of the snake making it more difficult to negotiate bends in the pipe.
3. The coupling segments may separate, leaving a length of snake in the pipe. Retrieval of the lost piece may be quite costly.